[BUG] TypeScript not working with "type": "module" // Unknown file extension ".ts"

[sonntag-philipp]

Context

• Playwright Version: 1.23.4
• Operating System: Windows
• Node.js version: 14.20.0 and > 16
• Browser: All, Chromium, Firefox, WebKit
• Extra: I used nvm for Windows to switch the NodeJS versions.

Console log

C:\Users\psn\Desktop\playwright-module-test> node --version
v16.16.0
C:\Users\psn\Desktop\playwright-module-test> npx playwright test
npm WARN config global `--global`, `--local` are deprecated. Use `--location=global` instead.
(node:9712) ExperimentalWarning: --experimental-loader is an experimental feature. This feature could change at any time(Use `node --trace-warnings ...` to show where the warning was created)

Running 3 tests using 3 workers

  3 passed (9s)

To open last HTML report run:

  npx playwright show-report

C:\Users\psn\Desktop\playwright-module-test> node --version
v14.20.0
C:\Users\psn\Desktop\playwright-module-test> npx playwright test
TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".ts" for C:\Users\psn\Desktop\playwright-module-test\playwright.config.ts
    at new NodeError (internal/errors.js:322:7)
    at Loader.defaultGetFormat [as _getFormat] (internal/modules/esm/get_format.js:71:15)
    at Loader.getFormat (internal/modules/esm/loader.js:105:42)
    at Loader.getModuleJob (internal/modules/esm/loader.js:243:31)
    at Loader.import (internal/modules/esm/loader.js:177:17)
    at Loader._requireOrImport (C:\Users\psn\Desktop\playwright-module-test\node_modules\@playwright\test\lib\loader.js:275:28)
    at Loader._requireOrImportDefaultObject (C:\Users\psn\Desktop\playwright-module-test\node_modules\@playwright\test\lib\loader.js:290:18)
    at Loader.loadConfigFile (C:\Users\psn\Desktop\playwright-module-test\node_modules\@playwright\test\lib\loader.js:79:20)
    at Runner.loadConfigFromResolvedFile (C:\Users\psn\Desktop\playwright-module-test\node_modules\@playwright\test\lib\runner.js:96:12)
    at runTests (C:\Users\psn\Desktop\playwright-module-test\node_modules\@playwright\test\lib\cli.js:153:27)
    at Ai.<anonymous> (C:\Users\psn\Desktop\playwright-module-test\node_modules\@playwright\test\lib\cli.js:70:7) {
  code: 'ERR_UNKNOWN_FILE_EXTENSION'
}
C:\Users\psn\Desktop\playwright-module-test>

package.json

{
  "name": "playwright-module-test",
  "version": "1.0.0",
  "description": "",
  "type": "module",
  "main": "index.js",
  "scripts": {},
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "@playwright/test": "^1.23.4"
  }
}

Describe the bug
The TypeScript support in combination with "type": "module" seems to be only working in NodeJS >= v16.
Combining TypeScript with "type": "commonjs" also worked in NodeJS v14.

I don't think that this is a big problem as the current LTS version is 16. The documentation in terms of the TypeScript support should be updated I guess so others don't waste time looking for a solution. Currently, the trouble shooting area in the documentation only sets NodeJS v14 as minimum requirement under which this case does not work anymore.

[dgozman]

@sonntag-philipp Indeed, "type": "module" mode only works with Node >= 16. Let me update the docs.

[gunters63]

I have:

$ node -v
v16.17.0

and

 "@playwright/test": "^1.25.1

here and still have the same problem:

$ npx playwright test

Running 0 tests using 0 workers

TypeError: Unknown file extension ".ts" for D:\proj\AtlasCopco\EnsoUi\apps\ui-docs-v1\tests\snapshot.spec.ts

    at async Promise.all (index 0)
=================
 no tests found.
=================


  1 error was not a part of any test, see above for details

Only when I remove "type": "module" from package.json it works.

[fedetibaldo]

This hasn't been resolved. It's still an issue to the present date. See https://github.com/fedetibaldo/playwright-typescript-module-bug for a minimal reproduction